Emergent parametric resonances and time-crystal phases in driven BCS systems
Abstract
We study the out-of-equilibrium dynamics of a Bardeen-Cooper-Schrieffer condensate subject to a periodic drive. We demonstrate that the combined effect of drive and interactions results in emerging parametric resonances, analogous to a vertically driving pendulum. In particular, Arnold tongues appear when the driving frequency matches , with a natural number, and the equilibrium gap parameter. Inside the Arnold tongues we find a commensurate time-crystal condensate which retains the symmetry breaking of the parent superfluid/superconducting phase and shows an additional time-translational symmetry breaking. Outside these tongues, the synchronized collective Higgs mode found in quench protocols is stabilized without the need of a strong perturbation. Our results are directly relevant to cold-atom and condensed-matter systems and do not require very long energy relaxation times to be observed.
Cite
@article{arxiv.2107.09683,
title = {Emergent parametric resonances and time-crystal phases in driven BCS systems},
author = {H. P. Ojeda Collado and Gonzalo Usaj and C. A. Balseiro and Damián H. Zanette and José Lorenzana},
journal= {arXiv preprint arXiv:2107.09683},
year = {2021}
}